DOCSLIB.ORG

Strange Matter and Kaon to Pion Ratio in the SU(3) Polyakov–Nambu–Jona-Lasinio Model

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Strange Matter and Kaon to Pion Ratio in the SU(3) Polyakov–Nambu–Jona-Lasinio Model PHYSICAL REVIEW C 99, 045201 (2019) Strange matter and kaon to pion ratio in the SU(3) Polyakov–Nambu–Jona-Lasinio model A. V. Friesen, Yu. L. Kalinovsky, and V. D. Toneev Bogoliubov Laboratory of Theoretical Physics (BLTP), Joint Institute for Nuclear Research, 141982 Dubna, Russia (Received 6 September 2018; published 2 April 2019) The behavior of strange matter in the frame of the SU(3) Polyakov-loop extended Nambu–Jona-Lasinio (PNJL) model including the UA(1) anomaly is considered. We discuss the appearance of a peak in the ratio of the number of strange mesons to nonstrange mesons known as the “horn.” The PNJL model gives a schematic description of the chiral phase transition and meson properties at finite temperature and density. By using the model, we can show that the splitting of kaon and antikaon masses appears as a result of the introduction of + + − − √ density. This may explain the difference in the K /π ratio and the K /π ratio at low sNN and their tendency √ + + to the same value at high sNN. We also show that the rise in the ratio K /π appears near the critical endpoint when we build the K+/π + ratio along the phase-transition diagram and it can be considered as a critical region signal. DOI: 10.1103/PhysRevC.99.045201 I. INTRODUCTION The strangeness suppression in pp collisions can result from insufficient time and space of colliding and the impossi- The study of matter formed during the collision of heavy bility of reaching the statistical equilibrium of strange flavor ions at high energies is currently of significant interest in high- with light quarks. energy physics. Much interest still focuses on the search of the An exact theoretical reproduction of the horn in the K/π critical endpoint and phase transition in hot and dense matter. ratio still does not exist. The microscopic transport model The search for quark-gluon plasma (QGP) where hadrons dis- that includes only the hadron phase and does not include the solve into interacting gluons and quarks is difficult due to the quark-gluon phase cannot reproduce experimental data [8–12] short lifetime of the QCD phase. It is needed to find sensible and, as a result, in the works [3,13] the authors suggest that probes for the transition to the QGP phase (i.e., deconfinement such a peak in the ratio can be explained as the onset of transition and the chiral symmetry restoration). One of the deconfinement. suggested signals was the strangeness enhancement which The statistical model of early stages (SMES) considers a was explained through the interactions between partons in slow increase and the following jump in the ratio of strange- QGP. to-nonstrange particle production as a result of the decon- Intriguing results were obtained from PbPb and AuAu finement transition. According to the SMES, at low collision collisions: a structure in the ratio of the positive charged energies confined matter is produced, and the increase in the kaon to the positive charged pion, named the “horn” (see ratio is due the low T of the early stage and the large mass of Fig. 1), was found. The horn was first described by the NA49 strange particles. When the deconfinement transition occurs Collaboration [1] and the work aroused significant interest. the strange quarks mass tends to its current mass (ms < T ) and Investigations at energies from 7 to 200 AGeV were made by the strangeness yield becomes independent of energy in the the (Relativistic Heavy Ion Collider Beam Energy Scan) [2] QGP (the “jump” from a high value of the ratio to its constant and it was shown that the data can be placed on the same curve value) [13]. [1,3–5]. Such enhancement was also observed in the ratio of Success in the description of experimental data was other positive charged strange particles to the positive charged achieved when the partial restoration of chiral symmetry [14] nonstrange pions. At that time, the horn was not observed was added in the transport model. In the work the primary in- −/π − in the ratio of negative charged particles K [6]. In the teraction was described through the mechanism of excitation + +/π + p p collision, the K ratio shows smooth behavior and decay of color objects—strings. The function of the string [3,6,7]. fragmentation includes the dependence on the baryon density, thus modelling the mechanism of the partial chiral symmetry restoration [14,15]. The authors showed that partial chiral symmetry restoration is responsible for the quick increase in the K+/π + ratio at low energies and its decrease with Published by the American Physical Society under the terms of the increasing energy (they explained this decrease as a result of Creative Commons Attribution 4.0 International license. Further chiral condensate destruction). distribution of this work must maintain attribution to the author(s) The qualitative reproduction of the peak in the energy and the published article’s title, journal citation, and DOI. Funded dependence of the kaon to pion ratio was obtained in the by SCOAP3. statistical model, which includes hadron resonances and the σ 2469-9985/2019/99(4)/045201(7) 045201-1 Published by the American Physical Society A. V. FRIESEN, YU. L. KALINOVSKY, AND V. D. TONEEV PHYSICAL REVIEW C 99, 045201 (2019) described by the effective potential U(, ¯ ; T ): μ L = q¯(iγ Dμ − mˆ − γ0μ)q 1 8 + g [(q ¯λaq)2 + (¯qiγ λaq)2] 2 S 5 a=0 +gD{det[q ¯(1 + γ5)q] + det[q ¯(1 − γ5)q]} − U(, ¯ ; T ), (1) where q = (u, d, s) is the quark field with three flavors, Nf = a 3, and three colors, Nc= 3, λ are the Gell–Mann matrices, 0 2 μ μ μ = , ,..., λ = μ = ∂ − a 0 1 8, 3 I and D iA , where A is λ √ the gauge field with A0 =−iA and Aμ(x) = g Aμ a absorbs FIG. 1. The K+/π + and K−/π − ratio as the s function for 4 S a 2 NN the strong interaction coupling. Pb + Pb and Au + Au central collisions [1,3–5]. Blue circles are the + + The effective potential U (, ¯ ; T ) depends on tempera- K /π ratio for pp collisions. ture T , the Polyakov loop field and its complex conjugate ¯ , which can be obtained through the expectation value of the meson. This type of model implies the existence of the critical Polyakov line [23,24]: temperature for hadrons, which plays the role of the hadron phase transition [16]. −→ 1 −→ ( x ) = TrcL( x ), (2) The SU(3) Nambu–Jona-Lasinio (NJL) model with the Nc Polyakov loop (PNJL model) seems to be most promising as an instrument for describing the chiral phase transition, where the deconfinement properties, and the existence of quarks β −→ −→ and hadron states [17–19]. The chiral symmetry breaking in L x = Pexp i dτA4( x ,τ) . (3) the model is explained through a mechanism of adding the 0 chiral condensate to the current quark. The Polyakov loop extended model in addition to the chiral transition takes into The Polyakov loop field is the order parameter for Z3- → account the deconfinement transition which is described by symmetry restoration, which is restored as 0 (con- → the Polyakov loop. The phase diagram of the PNJL model finement) and broken as 1 (deconfinement) [25]. The , corresponds to its modern concept: at low temperature and effective potential U ( ¯ ; T ) has to reproduce lattice QCD high chemical potential the system suffers a first-order phase data in the gauge sector [26] and must satisfy the Z3 center transition. At high temperature and low chemical potential in symmetry. Based on these suggestions one can choose any system the chiral phase transition line is a crossover [17,19]. form of the potential [17,24,27]. In this work the following The disadvantage of the model is that the critical temperature general polynomial form is used [24]: of the crossover transition at low chemical potential in the U , ¯ PNJL model is higher than in lattice QCD, T = 154(9) [20], ; T b2(T ) b3 b4 c =− ¯ − (3 + ¯ 3) + (¯ )2, and the temperature of the critical endpoint (CEP) is lower T 4 2 6 4 than in other models [20–22]. 2 3 T0 T0 T0 We address this paper to the problem of the kaon to pion b2(T ) = a0 + a1 + a2 + a3 . (4) ratio in the context of the SU(3) PNJL model. In Sec. II the T T T formalism of the PNJL model and the behavior of mesons For the effective potential the following parameters were and quarks at zero chemical potential is discussed. The PNJL chosen: T = 0.19 GeV, a = 6.75, a =−1.95, a = 2.625, model generalized to finite chemical potential is presented in 0 0 1 2 a =−7.44, b = 0.75, b = 7.5[24]. The grand potential Sec. III. In Sec. IV, the results are discussed and conclusions 3 3 4 density for the PNJL model in the mean-field approximation are given. can be obtained from the Lagrangian density(1)[28]: 2 II. MODEL FORMALISM = U , ¯ ; T + gS q¯iqi + 4gDq¯uqu i=u,d,s We consider the Polyakov-loop extended SU(3) Nambu– Jona-Lasinio model with scalar-pseudoscalar interaction d3 p ×q¯d qd q¯sqs−2Nc Ei and the t’Hooft interaction, which breaks UA(1) symme- (2π )3 ⊗ i=u,d,s try [18,19]. The global SU(3) SU(3) chiral symmetry of 3 the Lagrangian is obviously broken upon introducing the d p + − = , , − 2T [N (E ) + N (E )], (5) nonzero current quark massesm ˆ diag(mu md ms ), and the (2π )3 i i i=u,d,s confinement and deconfinement properties (Z3 symmetry) are 045201-2 STRANGE MATTER AND KAON TO PION RATIO IN THE … PHYSICAL REVIEW C 99, 045201 (2019) with the functions To obtain the value of the Polyakov loop field , ¯ , one needs to minimize the grand potential over its parameters + † −β(Ei−μ) N (Ei ) = Trc ln 1 + L e ∂ ∂ −βE + −βE + −3βE + = 0, = 0.
Load more

Recommended publications
  • The Particle World
    The Particle World ² What is our Universe made of? This talk: ² Where does it come from? ² particles as we understand them now ² Why does it behave the way it does? (the Standard Model) Particle physics tries to answer these ² prepare you for the exercise questions. Later: future of particle physics. JMF Southampton Masterclass 22–23 Mar 2004 1/26 Beginning of the 20th century: atoms have a nucleus and a surrounding cloud of electrons. The electrons are responsible for almost all behaviour of matter: ² emission of light ² electricity and magnetism ² electronics ² chemistry ² mechanical properties . technology. JMF Southampton Masterclass 22–23 Mar 2004 2/26 Nucleus at the centre of the atom: tiny Subsequently, particle physicists have yet contains almost all the mass of the discovered four more types of quark, two atom. Yet, it’s composite, made up of more pairs of heavier copies of the up protons and neutrons (or nucleons). and down: Open up a nucleon . it contains ² c or charm quark, charge +2=3 quarks. ² s or strange quark, charge ¡1=3 Normal matter can be understood with ² t or top quark, charge +2=3 just two types of quark. ² b or bottom quark, charge ¡1=3 ² + u or up quark, charge 2=3 Existed only in the early stages of the ² ¡ d or down quark, charge 1=3 universe and nowadays created in high energy physics experiments. JMF Southampton Masterclass 22–23 Mar 2004 3/26 But this is not all. The electron has a friend the electron-neutrino, ºe. Needed to ensure energy and momentum are conserved in ¯-decay: ¡ n ! p + e + º¯e Neutrino: no electric charge, (almost) no mass, hardly interacts at all.
    [Show full text]
  • Particle Physics Dr Victoria Martin, Spring Semester 2012 Lecture 12: Hadron Decays
    Particle Physics Dr Victoria Martin, Spring Semester 2012 Lecture 12: Hadron Decays !Resonances !Heavy Meson and Baryons !Decays and Quantum numbers !CKM matrix 1 Announcements •No lecture on Friday. •Remaining lectures: •Tuesday 13 March •Friday 16 March •Tuesday 20 March •Friday 23 March •Tuesday 27 March •Friday 30 March •Tuesday 3 April •Remaining Tutorials: •Monday 26 March •Monday 2 April 2 From Friday: Mesons and Baryons Summary • Quarks are confined to colourless bound states, collectively known as hadrons: " mesons: quark and anti-quark. Bosons (s=0, 1) with a symmetric colour wavefunction. " baryons: three quarks. Fermions (s=1/2, 3/2) with antisymmetric colour wavefunction. " anti-baryons: three anti-quarks. • Lightest mesons & baryons described by isospin (I, I3), strangeness (S) and hypercharge Y " isospin I=! for u and d quarks; (isospin combined as for spin) " I3=+! (isospin up) for up quarks; I3="! (isospin down) for down quarks " S=+1 for strange quarks (additive quantum number) " hypercharge Y = S + B • Hadrons display SU(3) flavour symmetry between u d and s quarks. Used to predict the allowed meson and baryon states. • As baryons are fermions, the overall wavefunction must be anti-symmetric. The wavefunction is product of colour, flavour, spin and spatial parts: ! = "c "f "S "L an odd number of these must be anti-symmetric. • consequences: no uuu, ddd or sss baryons with total spin J=# (S=#, L=0) • Residual strong force interactions between colourless hadrons propagated by mesons. 3 Resonances • Hadrons which decay due to the strong force have very short lifetime # ~ 10"24 s • Evidence for the existence of these states are resonances in the experimental data Γ2/4 σ = σ • Shape is Breit-Wigner distribution: max (E M)2 + Γ2/4 14 41.
    [Show full text]
  • Strange Jet Tagging
    1 Strange Jet Tagging Yuichiro Nakai T. D. Lee Institute & Shanghai Jiao Tong U. Based on YN, D. Shih and S. Thomas, 2003.09517 [hep-ph]. Higgs and Flavor, EF02, Snowmass, August 2020 2 Jets at colliders Jet : collimated bunch of hadrons as the signatures of quarks and gluons produced in high-energy collisions ✓ QCD partons are never observed isolated due to confinement. ✓ They give cascades of radiation (parton shower) by QCD processes. ✓ Hadrons are formed at ∼ ΛQCD Understanding jets is a key ingredient of physics measurements and new physics searches at colliders. What initial parton produces a jet ? 3 Quark and Gluon Tagging Top quark Gluon S. Yang, talk slide More constituents with more uniform Jet mass, N-subjettiness, … energy fragmentation and wider. Bottom/Charm Up-type vs Down-type Look for a displaced pT -weighted jet charge (secondary) vertex. 1 Qi Q (p j )κ κ = jet κ ∑ j T (pT ) j∈jet Wikipedia The last missing piece : Strange quark tagging? 4 Tagging Strategy • Strange vs Gluon We can expect the same thing as quark/gluon discrimination. S. Yang, talk slide More constituents with more uniform • Strange vs Up energy fragmentation and wider. We can expect the same thing as up/down discrimination. pT -weighted jet charge 1 Qi = Q (p j )κ κ (p jet )κ ∑ j T • Strange vs Down T j∈jet Possible ?? Main theme of Both are quarks with the same charge. this talk 5 Tagging Strategy CMS experiment at the LHC Tracker : trajectories of charged particles ECAL : energy of electrons and photons HCAL : energy deposits of hadrons 6 Tagging Strategy
    [Show full text]
  • Charm and Strange Quark Contributions to the Proton Structure
    Report series ISSN 0284 - 2769 of SE9900247 THE SVEDBERG LABORATORY and \ DEPARTMENT OF RADIATION SCIENCES UPPSALA UNIVERSITY Box 533, S-75121 Uppsala, Sweden http://www.tsl.uu.se/ TSL/ISV-99-0204 February 1999 Charm and Strange Quark Contributions to the Proton Structure Kristel Torokoff1 Dept. of Radiation Sciences, Uppsala University, Box 535, S-751 21 Uppsala, Sweden Abstract: The possibility to have charm and strange quarks as quantum mechanical fluc- tuations in the proton wave function is investigated based on a model for non-perturbative QCD dynamics. Both hadron and parton basis are examined. A scheme for energy fluctu- ations is constructed and compared with explicit energy-momentum conservation. Resulting momentum distributions for charniand_strange quarks in the proton are derived at the start- ing scale Qo f°r the perturbative QCD evolution. Kinematical constraints are found to be important when comparing to the "intrinsic charm" model. Master of Science Thesis Linkoping University Supervisor: Gunnar Ingelman, Uppsala University 1 kuldsepp@tsl .uu.se 30-37 Contents 1 Introduction 1 2 Standard Model 3 2.1 Introductory QCD 4 2.2 Light-cone variables 5 3 Experiments 7 3.1 The HERA machine 7 3.2 Deep Inelastic Scattering 8 4 Theory 11 4.1 The Parton model 11 4.2 The structure functions 12 4.3 Perturbative QCD corrections 13 4.4 The DGLAP equations 14 5 The Edin-Ingelman Model 15 6 Heavy Quarks in the Proton Wave Function 19 6.1 Extrinsic charm 19 6.2 Intrinsic charm 20 6.3 Hadronisation 22 6.4 The El-model applied to heavy quarks
    [Show full text]
  • Strangeness Content of the Pion in the U(3) Nambu-Jona-Lasinio Model
    Strangeness content of the pion in the U(3) Nambu-Jona-Lasinio model F´abioL. Braghin Instituto de F´ısica,Federal University of Goias, Av. Esperan¸ca,s/n, 74690-900, Goi^ania,GO, Brazil September 6, 2021 Abstract The Nambu-Jona-Lasinio model is considered with flavor-dependent coupling constants ¯ ¯ ¯ ¯ 2 Gij ( λi )( λj ) + ( iγ5λi )( iγ5λj ) for i; j = 0; 1::Nf − 1, and Nf = 3. A self consistent calculation of quark effective masses and coupling constants is performed making the strange quark effective mass to vary considerably. Quantum mechanical mixings between up, down and strange constituent quarks yields a strangeness content of the light u and d quarks constituent and of the pions. DIfferent estimates for the strangeness contribution for the pion mass are provided. 1 Introduction Hadron structure involves a large number of degrees of freedom and intrincated phenomena. Consequently their description with analytical methods in Quantum Chromodynamics presents many difficulties that usually require some approximative schemes being also possible to resort to effective models usually valid within a range of a variable, usually energy, associated to some physical scale. In spite of the limitations of an effective model, when compared to first principles calculations, one might expect that improvements eventually may produce a framework hoppefully comparable to effective field theories (EFT) if fundamental properties of QCD are taken into account by introducing the correct degrees of freedom in a suitable and correct way. Besides that, effective models can show very clearly the main connections between observables and the corresponding relevant degrees of freedom. The quark-level Nambu-Jona-Lasinio model (NJL) arXiv:2108.02748v2 [hep-ph] 3 Sep 2021 [1, 2, 3] captures some important features of quark dynamics and it has shown to be appropriate to describe several aspects of hadrons whenever Dynamical Chiral Symmetry Breaking (DChSB) plays an important role.
    [Show full text]
  • Quarks and Their Discovery
    Quarks and Their Discovery Parashu Ram Poudel Department of Physics, PN Campus, Pokhara Email: [email protected] Introduction charge (e) of one proton. The different fl avors of Quarks are the smallest building blocks of matter. quarks have different charges. The up (u), charm They are the fundamental constituents of all the (c) and top (t) quarks have electric charge +2e/3 hadrons. They have fractional electronic charge. and the down (d), strange (s) and bottom (b) quarks Quarks never exist alone in nature. They are always have charge -e/3; -e is the charge of an electron. The found in combination with other quarks or antiquark masses of these quarks vary greatly, and of the six, in larger particle of matter. By studying these larger only the up and down quarks, which are by far the particles, scientists have determined the properties lightest, appear to play a direct role in normal matter. of quarks. Protons and neutrons, the particles that make up the nuclei of the atoms consist of quarks. There are four forces that act between the quarks. Without quarks there would be no atoms, and without They are strong force, electromagnetic force, atoms, matter would not exist as we know it. Quarks weak force and gravitational force. The quantum only form triplets called baryons such as proton and of strong force is gluon. Gluons bind quarks or neutron or doublets called mesons such as Kaons and quark and antiquark together to form hadrons. The pi mesons. Quarks exist in six varieties: up (u), down electromagnetic force has photon as quantum that (d), charm (c), strange (s), bottom (b), and top (t) couples the quarks charge.
    [Show full text]
  • Mass Generation Via the Higgs Boson and the Quark Condensate of the QCD Vacuum
    Pramana – J. Phys. (2016) 87: 44 c Indian Academy of Sciences DOI 10.1007/s12043-016-1256-0 Mass generation via the Higgs boson and the quark condensate of the QCD vacuum MARTIN SCHUMACHER II. Physikalisches Institut der Universität Göttingen, Friedrich-Hund-Platz 1, D-37077 Göttingen, Germany E-mail: [email protected] Published online 24 August 2016 Abstract. The Higgs boson, recently discovered with a mass of 125.7 GeV is known to mediate the masses of elementary particles, but only 2% of the mass of the nucleon. Extending a previous investigation (Schumacher, Ann. Phys. (Berlin) 526, 215 (2014)) and including the strange-quark sector, hadron masses are derived from the quark condensate of the QCD vacuum and from the effects of the Higgs boson. These calculations include the π meson, the nucleon and the scalar mesons σ(600), κ(800), a0(980), f0(980) and f0(1370). The predicted second σ meson, σ (1344) =|ss¯, is investigated and identified with the f0(1370) meson. An outlook is given on the hyperons , 0,± and 0,−. Keywords. Higgs boson; sigma meson; mass generation; quark condensate. PACS Nos 12.15.y; 12.38.Lg; 13.60.Fz; 14.20.Jn 1. Introduction adds a small additional part to the total constituent- quark mass leading to mu = 331 MeV and md = In the Standard Model, the masses of elementary parti- 335 MeV for the up- and down-quark, respectively [9]. cles arise from the Higgs field acting on the originally These constituent quarks are the building blocks of the massless particles. When applied to the visible matter nucleon in a similar way as the nucleons are in the case of the Universe, this explanation remains unsatisfac- of nuclei.
    [Show full text]
  • Masses of Scalar and Axial-Vector B Mesons Revisited
    Eur. Phys. J. C (2017) 77:668 DOI 10.1140/epjc/s10052-017-5252-4 Regular Article - Theoretical Physics Masses of scalar and axial-vector B mesons revisited Hai-Yang Cheng1, Fu-Sheng Yu2,a 1 Institute of Physics, Academia Sinica, Taipei 115, Taiwan, Republic of China 2 School of Nuclear Science and Technology, Lanzhou University, Lanzhou 730000, People’s Republic of China Received: 2 August 2017 / Accepted: 22 September 2017 / Published online: 7 October 2017 © The Author(s) 2017. This article is an open access publication Abstract The SU(3) quark model encounters a great chal- 1 Introduction lenge in describing even-parity mesons. Specifically, the qq¯ quark model has difficulties in understanding the light Although the SU(3) quark model has been applied success- scalar mesons below 1 GeV, scalar and axial-vector charmed fully to describe the properties of hadrons such as pseu- mesons and 1+ charmonium-like state X(3872). A common doscalar and vector mesons, octet and decuplet baryons, it wisdom for the resolution of these difficulties lies on the often encounters a great challenge in understanding even- coupled channel effects which will distort the quark model parity mesons, especially scalar ones. Take vector mesons as calculations. In this work, we focus on the near mass degen- an example and consider the octet vector ones: ρ,ω, K ∗,φ. ∗ ∗0 eracy of scalar charmed mesons, Ds0 and D0 , and its impli- Since the constituent strange quark is heavier than the up or cations. Within the framework of heavy meson chiral pertur- down quark by 150 MeV, one will expect the mass hierarchy bation theory, we show that near degeneracy can be quali- pattern mφ > m K ∗ > mρ ∼ mω, which is borne out by tatively understood as a consequence of self-energy effects experiment.
    [Show full text]
  • Quark Masses 1 66
    66. Quark masses 1 66. Quark Masses Updated August 2019 by A.V. Manohar (UC, San Diego), L.P. Lellouch (CNRS & Aix-Marseille U.), and R.M. Barnett (LBNL). 66.1. Introduction This note discusses some of the theoretical issues relevant for the determination of quark masses, which are fundamental parameters of the Standard Model of particle physics. Unlike the leptons, quarks are confined inside hadrons and are not observed as physical particles. Quark masses therefore cannot be measured directly, but must be determined indirectly through their influence on hadronic properties. Although one often speaks loosely of quark masses as one would of the mass of the electron or muon, any quantitative statement about the value of a quark mass must make careful reference to the particular theoretical framework that is used to define it. It is important to keep this scheme dependence in mind when using the quark mass values tabulated in the data listings. Historically, the first determinations of quark masses were performed using quark models. These are usually called constituent quark masses and are of order 350MeV for the u and d quarks. Constituent quark masses model the effects of dynamical chiral symmetry breaking discussed below, and are not directly related to the quark mass parameters mq of the QCD Lagrangian of Eq. (66.1). The resulting masses only make sense in the limited context of a particular quark model, and cannot be related to the quark mass parameters, mq, of the Standard Model. In order to discuss quark masses at a fundamental level, definitions based on quantum field theory must be used, and the purpose of this note is to discuss these definitions and the corresponding determinations of the values of the masses.
    [Show full text]
  • Higgs Bosons with Large Couplings to Light Quarks
    YITP-SB-19-25 Higgs bosons with large couplings to light quarks Daniel Egana-Ugrinovic1;2, Samuel Homiller1;3 and Patrick Meade1 1C. N. Yang Institute for Theoretical Physics, Stony Brook University, Stony Brook, New York 11794, USA 2Perimeter Institute for Theoretical Physics, Waterloo, Ontario N2L 2Y5, Canada 3Department of Physics, Brookhaven National Laboratory, Upton, New York 11973, USA Abstract A common lore has arisen that beyond the Standard Model (BSM) particles, which can be searched for at current and proposed experiments, should have flavorless or mostly third-generation interactions with Standard Model quarks. This theoretical bias severely limits the exploration of BSM phenomenology, and is especially con- straining for extended Higgs sectors. Such limitations can be avoided in the context of Spontaneous Flavor Violation (SFV), a robust and UV complete framework that allows for significant couplings to any up or down-type quark, while suppressing flavor- changing neutral currents via flavor alignment. In this work we study the theory and phenomenology of extended SFV Higgs sectors with large couplings to any quark generation. We perform a comprehensive analysis of flavor and collider constraints of extended SFV Higgs sectors, and demonstrate that new Higgs bosons with large arXiv:1908.11376v2 [hep-ph] 31 Dec 2019 couplings to the light quarks may be found at the electroweak scale. In particular, we find that new Higgses as light as 100 GeV with order ∼ 0.1 couplings to first- or second-generation quarks, which are copiously produced at the LHC via quark fusion, are allowed by current constraints. Furthermore, the additional SFV Higgses can mix with the SM Higgs, providing strong theory motivation for an experimental program looking for deviations in the light quark{Higgs couplings.
    [Show full text]
  • THE STRANGE QUARK GLUON PLASMA Johann Rafelski
    621 THE STRANGE QUARK GLUON PLASMA Johann Rafelski", U. Heinzb, J. Letessierc, J. Sollfrankb and A. Tounsic "Department of Physics, University of Arizona, Tucson, AZ 85721 binstitut fiir Theoretische Physik der Universitiit,D-93040 Regensburg CLPTHE, Universite Paris 7, Tour 24, 5e et, 2 Place Jussieu, F-75251 CEDEX 05 ABSTRACT The mechanisms producing the strange quark flavor in high energy nuclear collisions are discussed and a dynamical picture developed for the build up of strangeness. The parameters characterizing strangeness phase space population are discussed and are related to measurable quantities. Circumstantial evidence for the formation of the deconfined phase (quark- gluon plasma, QGP) is presented, based on anomalous strange antibaryon abundances seen. It is argued that further experimental data will make the identificationof QGP definitive. 1. STRANGENESS AS AN OBSERVABLE OF QGP: Finding uncompromising signs of the transitory presence of the Quark-Gluon Plasma phase in the debris of the high energy nuclear collision has become the obsessive preoccupation of the high energy heavy ion theorists. The idea to use for this purpose the strange particles is not new and in the past dozen years strange particle production in heavy ion collisions and in particular their importance as diagnostic tool has been discussed a few times already at Rencontres de Moriond [l]; in the past 18 months considerable progress has occurred which allows us to return to the topic again, both in this report and in the parallel presentation of U. Heinz [2]. In order to appreciate these developments in full it is necessary to recall that the dynamical processes of strangeness production were from the beginning recognized as an essential element in the understanding of the high density matter in the central fireball.
    [Show full text]
  • Muon Bundles from the Universe* Maciej Rybczyński Institute of Physics, Jan Kochanowski University, Kielce, Poland
    Muon bundles from the Universe* Maciej Rybczyński Institute of Physics, Jan Kochanowski University, Kielce, Poland 17th International Conference on Strangeness in Quark Matter 10-15 July 2017 Utrecht, the Netherlands *based on P. Kankiewicz, MR, G. Wilk, and Z. Włodarczyk, ApJ 839 (2017) 31 [arXiv:1612.04749] Introduction ✓ Cosmic rays (CR) are particles coming from the Galaxy or outside the Galaxy reaching the Earth’s atmosphere. ✓ 90% protons, 9% He nuclei, 1% heavier nuclei ✓ Gammas, neutrinos ✓ Rate ~1000 particles hits the atmosphere per m2s CR are characterized by: ✓ Identity of the particle ✓ Energy (109 – 1020 eV) ✓ All arrival directions Cosmic ray physics with CERN experiments ✓Small detectors with respect to EAS experimets ✓ Low underground ✓ Detection of muons (only!) crossing the rock ✓ Short time of data taking These detectors are not designed to cosmic ray physics! Advantages: ▪ Detectors with very high performance ▪ Presence of magnetic field Detection of CR by CERN LEP experiments ALEPH: 130 m of rock, momentum muon threshold p > 70/cosθ ✓ underground scintillators, HCAL (horizontal area ~ 50 m2 ), TPC projected area ~ 16 m2 DELPHI: 100 m of rock, momentum muon threshold p > 52/cosθ ✓ Hadron calorimeter (horizontal area ~ 75 m2), muon barrel, TPC, ToF and outer detectors L3+C: 30 m of rock, momentum muon threshold p > 20/cosθ + surface array ✓ Scintillator surface array (200 m2), trigger, muon barrel (100 m2), hadron calorimeter, etc. COSMIC RAY ENERGY COVERAGE FROM 1014 – 1018 eV LEP results: muon multiplicity spectra ✔ These muon bundles are not well described (more than an order of magnitude above ALEPH: V. Avati et al., Astr. Phys.
    [Show full text]